Reznor R8HE Unit Installation Manual - Manual (Page 44)

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Preparing the pit
After pit location has been determined, the condensate
drain pit must be prepared for installation of the vertical
2” PVC vent pipe and insulated drain hose assembly. If
desired, remove any sod and top soil prior to digging for
later use at end of installation.
Vertical pit should be approximately 12”-14” in diameter
(or larger) for installation of the rock base and vertical
piping system to allow for proper drainage with a depth of
4”-6” below the regional frost line if possible. See
Figure
22 (page 46) .
Percolation Test (Optional)
A simple percolation test (not required) can be performed
to aide in determining if the diameter and depth for the pit
is suitable. It will allow you to simply observe how quickly
a known volume of water dissipates into the subsoil of a
drilled hole of known surface area. In general, sandy soil
will absorb more water than soil with a high concentration
of clay or where the water table is close to the surface.
1. Using
Table 20 , identify the approximate volume of water
being produced for the equipment being installed.
2. Pour a volume (V) of water large enough into the hole
capable of measuring the height.
(V) = (X) x Steady state Disposal Rate.
Example: For 5-Tube (100,000 BTU), if X=4 then
water volume (V) = 4 x 0.55 GPH = 2.20 Gallons.
3. Immediately measure the water level depth at the start
of the test (Y1Start) and then again after one hour
(Y2Final).
NOTE: The pit water level height change should be
greater than or equal to the disposal rate height change
or you may want to widen or deepen the hole if possible.
Pit Water Level Height Change = (Y1Start)-(Y2Final)
should be greater than or equal to Disposal Rate Height
Change= (Y1Start)/(X).
NOTE TO INSTALLER
READ THIS BEFORE YOU DIG!
Before you begin digging the pit for the condensate
drain line assembly, you may need to call to find out
where underground electric, gas, or other utilities
are located. Some state laws require that a locate
request be placed at least three (3) working days
prior to any digging projects. The utilities should
respond to your request by marking the approximate
location of their utilities or notifying you that they
have no utilities in your dig site area. After confirming
utility response, you can then proceed with your
excavation avoiding damages.
Vertical Drain Pipe Installation
1. After the pit has been dug out, pour the rock or chat
base to a level approximately 2” below the frost line.
Mix in 50% of the limestone rock, chat, or lime pellets
(if required by code) with the initial rock base.
2. Measure the distance between the top of the rock base
and bottom of ½” drain fitting.
3. Cut the field supplied 2” PVC pipe to the measured
length.
4. Cut the drain hose and insulation to the measured length
less 3” so the drain cannot become blocked.
5. Connect vinyl drain tube to the ½” barbed drain
connection at bottom of 2” PVC Tee and secure with
spring hose clamp.
6. Install flexible insulation over the entire length of drain
tube and cut away any excess, then secure at the top
with wire tie provided.
7. Place the 2” PVC pipe into the pit and work the drain
hose assembly into the pipe until the entire length is
inside and the PVC pipe is vertical.
8. Glue or use two 1/2” long screws (field supplied) to
secure the 2” PVC Tee to the unit horizontal vent pipe.
See Joint A in
Figure 22 . NOTE: Fastening the Tee
to the horizontal vent pipe with 1/2” screws will make
disassembly easier for future cleaning or inspection of
the drain / vent system.
9. While holding the 2” pipe completely vertical and
centered to the drain Tee, slowly backfill the pit around
the outside of the pipe. NOTE: Use the remaining rock
or chat until above the frost line then use remaining
backfill materials from the excavation area.
10. Continue to backfill the hole until 1”-2” above grade
level, then grade away to keep rain water from collecting
in the pit area as the ground settles over time. Add
any remaining top soil and sod back to pit location if
desired.
11. Proceed to Completing the Vent section ( page 45 ).
NOTE TO INSTALLER
READ THIS BEFORE YOU DIG!
Before you begin digging the trench for the
condensate drain line assembly, you may need to
call to find out where underground electric, gas, or
other utilities are located. Some state laws require
that a locate request be placed at least three (3)
working days prior to any digging projects. The
utilities should respond to your request by marking
the approximate location of their utilities or notifying
you that they have no utilities in your dig site area.
After confirming utility response, you can then
proceed with your excavation avoiding damages.
Horizontal Drain Trench Method
(Alternate Drain Construction)
If the surrounding area does not allow the digging of
a pit due to rock, dense clay soil, etc., the drain may
be applied in a shallower horizontal trench as long as
regional conditions allow. This type of application is not
Table 20. Condensate Disposal Rate
FURNACE HX SIZE
UNIT CONDENSATE DISPOSAL RATE
STEADY STATE
3 Tube – 60,000 KBTU 0.35 GPH
4 Tube – 80,000 KBTU 0.45 GPH
5 Tube – 96,000 KBTU 0.55 GPH